Compressing of fittings onto wire rope and the like



June 6, 1967 H. M. BENDER 3,323,205

COMPRESSING OF FITTINGS ONTO WIRE ROPE AND THE LIKE Filed July 9, 1954 1 Jaye/1 5 flaw/a7 Mange 12 Hem/er JIM W.

United States Patent 3,323,205 COMPRESSING 0F FITTINGS ONTO WIRE ROPE AND THE LIKE Harold Mervyn Bender, Charlton, London, England, assignor to British Ropes Limited, Doncaster, England Filed July 9, 1964, Ser. No. 381,406 Claims priority, application Great Britain, Nov. 15, 1963, 45,15 6/ 63 Claims. (Cl. 29-508) This invention relates to the compressing of fittings onto wire rope or strands or onto rods or bars.

The die arrangement described in patent specification No. 863,677 permits a large diametric section of metal to be reduced to a defined cross section without the creating of sharp fins where the compression dies meet. It would be advantageous on occasion to have an even larger diametric section compacted to the defined cross section, or even to a smaller section.

One arrangement shown in specification 863,677 is a four part segmental die arrangement having a cylindrical bore with edges of each individual die face bevelled to create a longitudinal rib on the compacted wire rope fitting. The combined angle of the bevellin-g brought about by closure of the dies is in the region of 130.

The present invention consists in a four part segmental die set, particularly for compressing fittings onto wire rope, in which each die face, when viewed in cross section, is substantially in the form of a pair of adjacent sides of a regular octagon.

The invention further consists in a method of pressing a fitting onto wire rope or strand, rod or bar, using a set of dies as set forth above, and in wire ropes or strands, rods or bars having fitting compressed thereonto by such a method.

Such a set gives rise to an octagonal bore (corner angles of 135) to the four-part segmental dies arrangement. This arrangement will permit the wire rope fitting to be rotated of a turn, or an odd multiple thereof between each successive bite of the dies during the compacting operation, thereby preventing the formation of a fin between the die faces. Any tendency to fin formation can be seen during the compacting operation, when pressure on the dies can be released and the fitting rotated so that the incipient fin is located in the angle between a pair of sides making up one of the dies.

Should there inadvertently be created a fin on complete closure of the dies, the fitting is rotated so as to compact the fin into correct form by aligning it with the centre of a segmental die face for a final compacting operation.

This invention will therefore permit larger diametric sections to be compacted to define cross sections without the creation of large sharp fins which may damage the compression dies and also have to be removed for safety before the fitting and wire rope can be put to service.

The drawing accompanying the provisional specification is a section through the working region of a set of dies formed according to the invention.

It can be seen from the drawing that each of four segmental quarter dies 1 has a working face 2 formed by mutually inclined plane surfaces, which, when viewed in cross section, form pairs of adjacent sides 3 of a regular octagon. When the dies are completely closed the set forms the complete octagonal section bore.

Patented June 6, 1967 The dies can be used for the attachment of fittings of a large variety of types onto rope, strand, rod or bar, but is particularly useful for attaching fittings to wire ropes. Such fittings may, for example, be terminals with screw threaded ends for. the purpose of attaching other fittings, such as fork nuts, eye nuts, turn-buckle barrels, rigging screw 'bodies, adjustable stops, nuts or T pieces. Alternatively the fittings may be terminals with integral fork nuts, eye nuts stops, T pieces etc. A further type of fitting is a jointing sleeve for rope, strand, rod or bar of similar or dissimilar dimensions.

Pairs of wire ropes had threaded terminals attached thereto using the dies described and fork and eye nuts were attached to the terminals and linked. The ropes thus joined were subjected to tensile destruction tests and it was found that the breaking strength in each case exceeded the nominal breaking strength of the rope and was more than 96% of the actual breaking strength.

For comparison it is mentioned that the strength of a hand splice is expected to be in the region of 87% of the breaking strength of the rope, and a fitting attached to a rope by rotary swaging may fail at a breaking strength of between 91 and 96% of the rope breaking strength.

In carrying out these tests it is to be notedthat the standard anchorage sockets for the rope samples under test were not suitable as they failed before the fittings, so that it was found necessary to use oversize sockets.

I claim:

1. A die set for pressing fittings onto rod, bar or wire rope or strand, comp-rising four dies each including a die face, the die faces each being, when viewed in cross section, in the form of a pair of adjacent sides of a regular octagon, whereby the set of dies, when closed, has a die face in the form of a regular octagon.

2. A method of pressing a fitting onto a rod, bar, wire rope or strand comprising compacting the fitting in a four part die set in which each die face, when viewed in cross section, is substantially in the form of a pair of adjacent sides of a regular octagon.

3. A method as claimed in claim 2 comprising the further steps of opening the die set, rotating the fitting through one-eighth of a turn, and further compacting the fitting.

4. A method as claimed in claim 2 comprising the further steps of opening the die set, rotating the fitting through an odd multiple of one-eighth of a turn, and further compacting the fitting.

5. A method as claimed in claim 2 in which the compacting is carried out in a number of separate stages and the fitting is rotated between stages so that the zone of the fitting in contact with a vertex formed in a die face in one stage is in contact with the junction between die faces in the succeeding stage.

References Cited UNITED STATES PATENTS 467,657 1/ 1892 Wood 72-402 2,288,086 6/ 1942 Gettig et al 72-421 3,154,978 11/1964 Baker 72402 

2. A METHOD OF PRESSING A FITTING ONTO A ROD, BAR, WIRE ROPE OR STRAND COMPRISING COMPACTING THE FITTING IN A FOUR PART DIE SET IN WHICH EACH DIE FACE, WHEN VIEWED IN CROSS SECTION, IS SUBSTANTIALLY IN THE FORM OF A PAIR OF ADJACENT SIDES OF A REGULAR OCTAGON. 